A phased array is a group of antennas in which the relative phases of the respective signals feeding the antennas are varied in such a way that the effective radiation pattern of the array is reinforced in a desired direction and suppressed in undesired directions. Phased arrays are extensively used in satellite communications, multipoint communications, radar systems, early warning and missile defense systems, etc., so they are employed in large quantities. The cost of phased arrays can range from US $150,000 (500 antennas) to US $1,000,000 (3000 antennas). In a conventional phased array system, the signal to be sent is divided into many branches using a power, splitter and each branch is then fed into a phase shifter (i.e. a phase shifter is a microwave component, which is used to delay the phase or timing of a sinusoidal signal) and followed by an antenna. The cost of a conventional phased array mainly depends on the cost of the phase shifters used. It has been estimated that almost half of the cost of a phased array is due to the cost of phase shifters. Because of the high cost of phase shifters, a significant amount of research has been performed to minimize the cost and improve the performance of phase shifters. In addition, conventional phased arrays result in very complex structures and suffer from high loss and mass.